21120033 has 24 divisors (see below), whose sum is σ = 31857696. Its totient is φ = 12342400.

The previous prime is 21120019. The next prime is 21120041. The reversal of 21120033 is 33002112.

It is a happy number.

It is not a de Polignac number, because 21120033 - 2⁴ = 21120017 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21120133) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 27373 + ... + 28133.

It is an arithmetic number, because the mean of its divisors is an integer number (1327404).

Almost surely, 2^21120033 is an apocalyptic number.

It is an amenable number.

21120033 is a deficient number, since it is larger than the sum of its proper divisors (10737663).

21120033 is a wasteful number, since it uses less digits than its factorization.

21120033 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 833 (or 804 counting only the distinct ones).

The product of its (nonzero) digits is 36, while the sum is 12.

The square root of 21120033 is about 4595.6537075807. The cubic root of 21120033 is about 276.4170731675.

Adding to 21120033 its reverse (33002112), we get a palindrome (54122145).

It can be divided in two parts, 211200 and 33, that multiplied together give a square (6969600 = 2640²).

The spelling of 21120033 in words is "twenty-one million, one hundred twenty thousand, thirty-three".